This invention relates generally to air conditioning systems and more particularly, to a condensation disposal system for a packaged terminal air conditioner. Warm air is frequently humid, i.e. it contains water vapor. During the operation of an air conditioning system in the cooling mode, the refrigerant evaporator system reduces the temperature of the air to a level below its dew point and water vapor condenses on the evaporator. Some means must be provided to dispose of this condensation. In small unit air conditioners, such as in a window or wall mounted room air conditioners, a common means to accomplish the disposal of condensation is to provide a condensation collection and drain path that connects the indoor and outdoor sections of the air conditioner. Condensation formed on the system evaporator drains into a collector in the indoor section and then flows to a location under or near the condenser fan in the outdoor section.
The present invention provides a condensation distribution device to pick up the condensation and cause it to flow onto the hot surface of the condenser system where the water evaporates. Such an arrangement eliminates the need for an inconvenient, unsightly and costly condensation drain from the air conditioner. This provides for an economical use of the condensation in that the energy necessary to evaporate the water is used to assist in the cooling of the warm refrigerant in the condenser, thus resulting in an improvement in system efficiency.
Common condensation distribution schemes include vortex impellers or aspirators, slinger rings, and mechanical pumps or specially designed fan blade tips. As described in U.S. Pat. No. 605,539 by Kenneth J. Meyer, issued Jul. 11, 2000, for window room air conditioners and packaged terminal air conditioners, it is most common to use a slinger arrangement associated with a condenser fan. In a typical slinger arrangement, a blow-through propeller fan coil configuration is used and the condensation collects at a location where the fan structure causes the condensation to be splashed onto the condenser coil, where it is evaporated, thereby, providing cooling to the condenser. The effectiveness of such a condensation disposal system, i.e. wherein a propeller fan is used to distribute the cold condensation generated by the indoor coil to be evaporated on the hot outdoor coil is dependent on many factors. The effectiveness is negligible because of the inequality of distribution of the condensation onto the condenser coil surface and contamination of this surface by salts or different impurities that occur in the condensation.
In U.S. Pat. 6,065,299 by Chen Tsai Chi issued May 23, 2000 for window room air conditioners it is proposed that a special mechanism located in front of the condenser be used, so that the condenser will be located between the mechanism and the cooling fan. The effectiveness of the mechanism is negligible because of the reduction of airflow through the condenser due to the increased hydraulic resistance to airflow passage through the condenser. The degree of this resistance could increase due to the contamination of the surface of the mechanism by impurities, which occur in the outside air.
Finally, since the full benefit of the use of condensation to cool the condenser coil is not gained for the reasons discussed herein, the condensing temperature is not lowered as much as would otherwise occur, thereby resulting in a higher evaporation temperature and less condensation being formed. The efficiency of the system will be reduced. Accordingly, the need exists for improving the device that increases the efficiency of air conditioners.
Briefly, in accordance with one aspect of the invention, a packaged terminal air conditioner is provided with a device for using condensation from the evaporator to reduce the energy consumption of an air conditioner. This device is placed in front of a condenser where air enters and is located between the condenser and fan feeding the condenser.
According to the first embodiment of the invention the device is comprised of several rods fixed on a bar. A porous material with a capillary structure such as ceramics, fabric, wire gauze net, and others covers the surfaces of the rods and bar. According to the second embodiment of the invention the device is comprised of one or several heat pipes. The cool ends of the pipes are covered by a porous material with a capillary structure such as ceramics, fabric, wire gauze net, and others. In the drawings as hereinafter described, preferred embodiments are depicted. However, various other modifications and alternate constructions can be made thereto without departing from the true spirit and scope of the invention.